1. Field of the Invention
The present invention relates generally to light assemblies and more particularly to heated light assemblies or use in vehicles which operate in cold weather wherein the lens of the light beam assembly becomes frosted over because of the cold conditions.
2. Description of the Prior Art
The integration of light emitting diodes (LEDs) in lamp assemblies are well known in the art. LED lamp assemblies for use on motor vehicles are also well known in the art. LED lamp assemblies have distinct advantages over incandescent bulbs, which are more commonly used. LED lamp assemblies have much longer lives, so their utility is longer, more reliable, and more cost efficient. One of the key advantages of LED-based lighting is its high efficiency based on the light produced (lumens) per unit of power used. Most LEDs require very little current and power, usually 30-60 milliwatts of electrical power. For practical general lighting applications, higher power is generally required (≧1 Watt), with operating currents beginning at 350 mA. While a conventional 60-100 watt incandescent lightbulb produces around 15 lumen per watt, advances in technology have produced white LED efficacy as high as between 131 Lm/W to 150 Lm/W, at 20 mA. In addition to being efficient, LEDs are also less expensive than standard, incandescent bulbs to manufacture, and the resulting light is stronger and even across the field of view because the LED lamp assembly reduces and effectively eliminates the diffraction pattern from standard, single bulb lamp assemblies, i.e., the alternating rings of bright and dim light are not present in multiple-LED lamp assemblies. The reliable, long-lasting, bright, clear light combined with low power utilization inherent in LED lamp assemblies make them highly desirable in motor vehicles.
An issue with lamp assemblies, of any type, on motor vehicles, is that motor vehicles are exposed to rapid temperature changes and inclement weather of many types, and this includes their lamp assemblies. Weather systems that involve ice, snow, freezing temperatures, and humidity pose a problem by hindering the luminous property of a lamp assembly by blocking the light from the exterior, such as covering the lamp with snow, or by blocking the light from the interior of the lamp, such as with condensation. It is inconvenient for a driver to continually wipe the snow, sleet and rain off the headlights of a vehicle and nearly impossible for a driver to remove the condensation on the interior of a light assembly without the time consuming process of completely disassembling the entire lamp. Numerous attempts have been made to address these issues. The following eighteen patents and published patent applications are relevant to the field of the present invention.
1. U.S. Pat. No. 1,816,299 issued to Luther E. Rynearson on Jul. 2, 1931 for “Glare Shield Attachment For Headlights” (hereafter the “Rynearson Patent”);
2. U.S. Pat. No. 1,925,423 issued to William H. Warhus, Jr. et al. on Sep. 5, 1933 for “Headlight” (hereafter the “Warhus Patent”);
3. U.S. Pat. No. 1,951,902 issued to John D. Dempsey on Mar. 20, 1934 for “Heater Attachment For Automobile Headlamps And The Like” (hereafter the “Dempsey Patent”);
4. U.S. Pat. No. 3,364,381 issued to Rosena E. Porter on Jan. 16, 1968 for “Vehicle Safety Lights” (hereafter the “Porter Patent”);
5. U.S. Pat. No. 3,406,282 issued to Harvey J. Kinch on Oct. 15, 1968 for “Headlamp Adapter Kit For Motor Vehicle” (hereafter the “Kinch Patent”);
6. U.S. Pat. No. 4,728,775 issued to George A. Van Straten on Mar. 1, 1988 for “Indicator Light Cover For Vehicles And The Like” (hereafter the “Straten Patent”);
7. U.S. Pat. No. 5,182,432 issued to Ulrich V. Lange et al. and assigned to Hella KG Hueck & Co. on Jan. 26, 1993 for “Crack Detector And Heating Circuit For Motor Vehicle Headlight Light Transmissive Shield” (hereafter the “Lange Patent”);
8. U.S. Pat. No. 5,558,431 issued to Andrew V. Wilson and assigned to Novation Research, Inc. on Sep. 24, 1996 for “Replaceable Warning Light Lens Protector” (hereafter the “Wilson Patent”);
9. U.S. Pat. No. 6,563,086 issued to Carl E. Meirndorf et al. on May 13, 2003 for “Vehicle Lights Defroster Device” (hereafter the “Meirndorf Patent”);
10. U.S. Pat. No. 6,601,983 issued to Vincent A. Runfola et al. on Aug. 5, 2003 for “Led Vehicular Light Assembly With Heater” (hereafter the “Runfola Patent”);
11. United States Published Patent Application No. 2004/0070339 issued Yoshihisa Suda et al. on Apr. 15, 2004 for “Vehicle Lamp” (hereafter the “Suda Published Patent Application”);
12. United States Published Patent Application No. 2006/0011598 issued to Yuji Yasuda on Jan. 19, 2006 for “Vehicular Lamp” (hereafter the “Yasuda Published Patent Application”);
13. United States Published Patent Application No. 2006/0104077 issued to Hirohiko Oshio et al. on May 18, 2006 for “Vehicular Lamp” (hereafter the “Oshio Published Patent Application”);
14. United States Published Patent Application No. 2006/0232972 issued to Mitsuyuki Mochizuki on Oct. 19, 2006 for “Method For Manufacturing A Vehicular Lamp And A Vehicular Lamp” (hereafter the “Mochizuki Published Patent Application”);
15. United States Published Patent Application No. 2006/0245202 issued to Cary Moreth et al. on Nov. 2, 2006 for “Vehicular Light Heater” (hereafter the “Moreth Published Patent Application”);
16. United States Published Patent Application No. 2007/0025105 issued to Takashi Inoue et al. on Feb. 1, 2007 for “Vehicular Lamp” (hereafter the “Inoue Published Patent Application”);
17. UK Patent Application No. 2,334,571 issued to Mark Rowalnd Yewman on Aug. 25, 1999 for “Light Fitting For A Vehicle Comprising Heating Element” (hereafter the “Yewman UK Patent Application”);
18. Patent Abstract of Japan No. 2002150812 issued to Takahata Yoshihiro on May 24, 2002 for “Headlamp For Vehicle” (hereafter the “Yoshihiro Patent Abstract of Japan”).
In reference to the Rynearson Patent, there is disclosed a glare shield for a headlight and the concept of incorporating a heating element into a glare shield. Specifically, the Rynearson Patent teaches a large semi-conical device having a base housing the heating means that is placed in front of the headlamp and is attached to the lens of the headlamp. The light from the headlamp passes through perforations in the base of the device to reduce the glare from the headlamp. The Rynearson Patent is big, bulky, unattractive, and significantly blocks the light from the headlamp, which light is particularly required during inclement weather when the device is to be used.
In reference to the Warhus Patent, there is disclosed a heating element within a headlamp for the purpose of melting snow and ice as it accumulates. The heating element is located within the headlamp and is placed between the light bulb and the outer lens. The heating element and the T-shaped brace that supports the heating element abuts the outer lens, and is unsightly and interferes with the appropriate illumination of the road during inclement conditions.
In reference to the Dempsey Patent, there is disclosed a heater attachment for automobile headlamps, which is placed over, around and in front of the lens of the headlamp. The heating element is a wire coil placed longitudinally in front of the headlamp, sandwiched between the lens of the headlamp and the lens of the Dempsey Patent.
In reference to the Porter Patent, there is disclosed specifically a taillight for vehicles with a heating element. The patent discloses a tail light having two incandescent light elements, one of which is of relatively high resistance and low illumination and can therefore function as both a heating and illuminating element. Further, this heating and illuminating element is directly connected to the ignition switch such that whenever the ignition switch is closed, i.e. the engine is on, the heating/lighting element is always on.
The Kinch Patent discloses an adapter designed specifically for the original 1960's Volkswagen Beetle automobile. The Kinch adapter is for after-market remodeling of the headlamp on the original Volkswagen Beetle to change the angle of the lamp, which can be from other manufacturers, from a position flush with the front bumper to a position wherein the face of the lamp is perpendicular to the street, which eliminates the glass shield that covered the sealed beam unit lamp and that easily freezes over. By removing this glass shield, by making the angle of the lens approximately 90 degrees from horizontal, and by using the ordinary heat generated from the normal operation of the sealed beam unit to function as a heater, the Kinch adapter is able to melt snow and ice from the headlamp and keep snow and ice off the headlamp.
The Van Straten Patent is an indicator light cover for vehicles which includes a heating element mounted to the cover. The heating element is placed in front of the illumination source and on the interior surface of the lens of the headlamp and is comprised of a flexible wire formed in concentric circular loops positioned in the grooves of the Fresnel-like lens that is the cover of the indicator light.
The Lange Patent discloses a crack monitoring system for the lens of a headlamp. The crack monitoring system has a secondary function of being a heating element for the headlamp having the heating element incorporated within the lens of the headlamp.
The Wilson Patent discloses an elongated lens, protector in the form of an attachment to the outer, leading surface of a lens of an emergency vehicle warning light located on the roof of the vehicle. A heating element can be added to the lens protector and resides on the exterior of the light between the lens of the emergency lights and the shield that is the lens protector.
The Meirndorf Patent discloses a cap for the tail lights of a school bus, covering the lens of the flashing lights of the bus and in which a heating element has been incorporated.
The Runfola Patent discloses a light assembly utilizing light emitting diodes, but the disclosed heating element is a two piece system by which a first heater, mounted on the board with the lights attaches to a second heating element mounted on the interior surface of the front lens.
The Suda Published Patent Application discloses a heating element added to the body of the vehicle lamp and which can be easily seen from outside the lamp.
The Yasuda Published Patent Application discloses a heating element embedded in the outer lens of the vehicular headlamp.
The Oshio Published Patent Application utilizes the heat from a single light emitting diode to melt ice and snow from the lens of the lamp.
The Mochizuki Published Patent Application discloses a headlamp having the heating element incorporated into the lens to melt snow and ice.
The Moreth Published Patent Application discloses a heating element that lies along the floor of the front cover of the light assembly.
The Inoue Published Patent Application discloses using gathering the heat from the light elements into a heat sink which is then brought forward to the lens to melt snow and ice.
The United Kingdom Published Application discloses a heating unit on the exterior surface of a lens of a headlamp.
The Yoshihiro Published Japanese Patent Application discloses a heating element that is printed on the lens to remove snow and ice deposits.
Generally, light assembly technology has been that of a sealed beam lamp of a single assembly, over which a front cover, usually of clear glass, is permanently attached. The sealed beam assembly, with the reflector, the front lens array and the bulb are all one unit that must be replaced together when the bulb burns out. The sealed beam lamp produces an intense oval pool of light with unfocused edges.
In addition, it can be seen that the prior art places a heating element in front of the light source, usually in a manner that impedes the light. The placement of a heating element in front of the light, in front of the lens or in front of the reflector plate, all have the same negative issues, that the result is usually ungainly and invariably unsightly light.